Re: Accessing database statistics

Ok, this all depends on how postgresql does this query. If it (behind 
the scenes) does a call to a system table which holds a field for the 
count of each table then fine - nice and efficient. However if this does 
a scan of the appropriate table and counts the number of tuples then 
returns this figure, then this is a really expensive operation, and I 
need this to be fast.

Tony

Duncan Adams (DNS) wrote:

> for the first part u might try 
>
> select count(*) from <table>;
>
> -----Original Message-----
> From: Tony Griffiths(RA) [mailto:griffitt@xxxxxxxxxxxx]
> Sent: Thursday, May 30, 2002 2:01 PM
> To: pgsql-novice@xxxxxxxxxxxxxx
> Subject: [NOVICE] Accessing database statistics
>
>
> Hi,
> I need to write a query that returns the number of rows currently stored 
> in a table. I presume that I issue a query against the system tables, 
> but don't know which one(s) to do this against. So a couple of questions:
>
> 1) With specific reference to my problem, how do I do this?
> 2) More generally, is there any where that gives detailed descriptions 
> of the system tables?
>
> Many thanks,
>
>
> Tony
>
>
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